Impact of dietary Na+ on glycyrrhetinic acid-like factors (kidney 11beta-(HSD2)-GALFs) in human essential hypertension.
Our previous studies have shown that human urine contains glycyrrhetinic acid-like factors (GALFs) that possess inhibitory activity against kidney 11beta-hydroxysteroid dehydrogenase isoform 2 (HSD2). The present studies were undertaken to determine the impact of dietary Na+ intake on the levels of kidney 11beta(HSD2)-GALFs. The excretion of kidney 11beta(HSD2)-GALFs in 24-hour urine samples of 30 unmedicated subjects (10 normotensive and 10 high/normal-renin and 10 low-renin essential hypertensive subjects) on both 200- and 10-mmol Na+ diets was studied. No differences in the urinary levels of kidney 11beta(HSD2)-GALFs were observed among the three groups on the high-Na+ diet. However, with a low-Na+ diet, the levels of kidney 11beta(HSD2)-GALFs were significantly increased in hypertensive subjects but not in normal subjects. Levels increased from 8.3+/-1.4 to 17.3+/-2.9 and 6.7+/-1.3 to 10.6+/-1.4 carbenoxolone sodium units/d in high/normal-renin (P=.01) and low-renin hypertensive subjects (P=.07), respectively; normal subjects changed from 8.0+/-1.9 to 10.6+/-2.4. The levels of kidney 11beta(HSD2)-GALFs were significantly higher in the high/normal-renin hypertensive subjects than in either the control normotensive subjects or the low-renin hypertensive subjects when challenged with the low-Na+ diet (P<.05 by Wilcoxon rank-sum test). The greater response of the high/normal-renin essential hypertensive subjects indicated that they may utilize kidney 11beta(HSD2)-GALFs when challenged with a low-Na+ diet, whereas the low-renin essential hypertensive subjects do not.
Morris
D J
DJ
Department of Pathology and Laboratory Medicine, The Miriam Hospital, Brown University School of Medicine, Providence, RI 02906, USA. dmorris@rihosp.edu
Lo
Y H
YH
Lichtfield
W R
WR
Williams
G H
GH
D042842:11-beta-Hydroxysteroid Dehydrogenases; D001794:Blood Pressure; D002851:Chromatography, High Pressure Liquid; D004039:Diet, Sodium-Restricted; D004791:Enzyme Inhibitors / Q000652:urine*; D006034:Glycyrrhetinic Acid / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000494:pharmacology / Q000652:urine*; D006801:Humans; D006913:Hydroxysteroid Dehydrogenases / Q000037:antagonists & inhibitors*; D006973:Hypertension / Q000503:physiopathology / Q000652:urine*; D007527:Isoenzymes / Q000037:antagonists & inhibitors; D007668:Kidney / Q000201:enzymology*; D012982:Sodium, Dietary
D004791:Enzyme Inhibitors; D007527:Isoenzymes; D012982:Sodium, Dietary; D006913:Hydroxysteroid Dehydrogenases; D042842:11-beta-Hydroxysteroid Dehydrogenases; D006034:Glycyrrhetinic Acid